Battilana, the Italian model who later wore a wire to catch Hollywood mogul Harvey Weinstein, had moved to America in 2012 because she felt threatened after testifying against the former prime minister. “I left Italy,” she told The Daily Beast. “I didn’t know what was going to happen. I took my brother to the Philippines. I know how my family has suffered. It has been devastating.”

But her friend Fadil, who was born in Morocco, decided to stay in Italy after testifying, write a tell-all book about her nights at Arcore, and pursue a civil lawsuit against the former PM and his cronies who, she said, had ruined her life. She was joined in the litigation by Battilana and another model who frequented Berlusconi's basement parties. Fadil last testified in court against Berlusconi in mid-January.

Now she's dead. And prosecutors in Milan have opened up a murder investigation. “What happened to Imane is very weird,” Ambra told The Daily Beast. “They say she was writing a book and now she got poisoned. It’s very creepy.”

Like many, Battilana suspects that Berlusconi and his henchmen had something to do with Fadil’s demise and worry about their own future. “They destroyed my name and I wanted to get it back,” she said. Now, she asks, “How can I stay safe?”

The 33-year-old Fadil was admitted into a Milan area hospital on Jan. 29 complaining of severe stomach pain. The doctors ruled out cancer and common diseases, and they even tested her for the bacterial infection leptospirosis after she told them there were mice in her apartment. They tested her makeup, her apartment, and possible contaminants in the hospital itself.

When test after test proved negative—and her condition slowly worsened—the pathologist called in scores of experts and started looking for something more sinister. But common poisons like arsenic weren't found in her blood. Finally, on her deathbed at the end of February, she told her brother Tarek and her lawyer Paolo Sevesi she was sure she was poisoned.

More extensive tests were conducted on her deteriorating body, finding elevated traces of metals like cobalt and nickel in her by-then-ravaged system. "It was a mixture of radioactive substances which are not normally available for purchase," Sevesi told The Daily Beast. On March 1, the model was dead and the homicide investigation begun.

Berlusconi, who has been investigated for witness tampering in four separate cases, which he denies and which have not yet gone to trial, was asked about the murder investigation by reporters last weekend. “Sorry,” he said about the woman's demise, but, “I didn't know her.”

Fadil testified back in 2012 when Berlusconi was on trial for paying an underage Moroccan girl, stage name Ruby the Heartbreaker, for sex. He was convicted and then acquitted of the charges because it could never be proved he knew Ruby's age.

When Fadil testified she detailed the wild nights at Berlusconi's mansion, which she said were filled with powerful men and young showgirls who often wore costumes. Fadil testified she had seen some girls dressed as Catholic nuns doing lap dances on Berlusconi cronies before stripping down to G-strings.

Fadil and others testified during a succession of “bunga bunga” trials that they were given envelopes with €2,000 ($2,270) in cash at the end of the night if they didn't participate in sex. Those who did got much more. One night when Berlusconi handed Fadil the envelope, he told her he hoped she “wasn't offended” by the paltry sum and implied that there was a way to earn more.

Fadil's book, which she had nearly finished, according to her brother, was filled with names of attendees.

She also testified at the time that at those parties she had met men who she thought were in the Russian secret service. During that time, Berlusconi and Russian President Vladimir Putin were best of friends. Who can forget Berlusconi bragging to a call girl that he was having sex with her on “Putin’s bed,” as she later testified?

It's no surprise that when Fadil died from what appears to have been an exotic toxin, many naturally thought that she might have suffered a fate similar to Sergei Skripal, who narrowly survived after he was poisoned with a Russian nerve agent, or Alexander Litvinenko, a former Russian spy killed in London by ingesting the radioactive isotope polonium 210.

After Fadil died, Sevesi alerted local prosecutor Francesco Greco, who urged the family not to announce the death until post-mortem tests could be done. Initial lab reports found elevated traces of certain minerals, but nothing they could identify. Greco ordered the samples be sent to a national lab in northern Italy. And over the weekend he also ordered armed guards to protect her corpse. “No one can see the body,” he ordered. “We can't risk contamination.”

Fadil’s lawyer suggested in a telephone interview with The Daily Beast that the investigators are not just worried that someone might try to destroy evidence. “It's possible they are at least as concerned that she might have been poisoned by something that is not safe for anyone exposed to her.”

Later this week, a full autopsy report including toxicology results from bone tissue is expected to be completed by Italy’s leading forensic pathologist and anthropologist, Cristina Cattaneo, who is only called in on the most important cases. The results either will answer some of the mysterious questions around the model's death—or produce even more.